/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.confignode.procedure.entity;

import org.apache.iotdb.confignode.procedure.env.TestProcEnv;
import org.apache.iotdb.confignode.procedure.exception.ProcedureException;
import org.apache.iotdb.confignode.procedure.exception.ProcedureSuspendedException;
import org.apache.iotdb.confignode.procedure.exception.ProcedureYieldException;
import org.apache.iotdb.confignode.procedure.impl.statemachine.StateMachineProcedure;

import java.io.DataOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.concurrent.atomic.AtomicInteger;

public class StuckSTMProcedure
        extends StateMachineProcedure<TestProcEnv, StuckSTMProcedure.TestState> {
    private int childCount = 0;

    public StuckSTMProcedure() {
    }

    public StuckSTMProcedure(int childCount) {
        this.childCount = childCount;
    }

    public enum TestState {
        STEP_1,
        STEP_2,
        STEP_3
    }

    @Override
    protected Flow executeFromState(TestProcEnv testProcEnv, TestState testState)
            throws ProcedureSuspendedException, ProcedureYieldException, InterruptedException {
        AtomicInteger acc = testProcEnv.getAcc();
        try {
            switch (testState) {
                case STEP_1:
                    acc.getAndAdd(1);
                    setNextState(TestState.STEP_2);
                    break;
                case STEP_2:
                    for (int i = 0; i < childCount; i++) {
                        SleepProcedure child = new SleepProcedure();
                        addChildProcedure(child);
                    }
                    setNextState(TestState.STEP_3);
                    break;
                case STEP_3:
                    acc.getAndAdd(-1);
                    return Flow.NO_MORE_STATE;
            }
        } catch (Exception e) {
            if (isRollbackSupported(testState)) {
                setFailure("proc failed", new ProcedureException(e));
            }
        }
        return Flow.HAS_MORE_STATE;
    }

    @Override
    protected boolean isRollbackSupported(TestState testState) {
        return true;
    }

    @Override
    protected void rollbackState(TestProcEnv testProcEnv, TestState testState)
            throws IOException, InterruptedException {
    }

    @Override
    protected TestState getState(int stateId) {
        return TestState.values()[stateId];
    }

    @Override
    protected int getStateId(TestState testState) {
        return testState.ordinal();
    }

    @Override
    protected TestState getInitialState() {
        return TestState.STEP_1;
    }

    @Override
    public void serialize(DataOutputStream stream) throws IOException {
        stream.writeInt(TestProcedureFactory.TestProcedureType.STUCK_STM_PROCEDURE.ordinal());
        super.serialize(stream);
        stream.writeInt(childCount);
    }

    @Override
    public void deserialize(ByteBuffer byteBuffer) {
        super.deserialize(byteBuffer);
        this.childCount = byteBuffer.getInt();
    }
}
